docs: def strip(self):
          """ Remove coordinates that are zero, the opposite of expand().
  
          ::
  
              >>> l = Location(pop=1, snap=0)
              >>> l.strip()
              <Location pop:1 >
              
          """
          result = []
          for k, v in self.items():
              if isinstance(v, tuple):
                  if v > (_EPSILON, ) * len(v) or v < (-_EPSILON, ) * len(v):
                      result.append((k, v))
              elif v > _EPSILON or v < -_EPSILON:
                  result.append((k, v))
          return self.__class__(result)